Self-priming centrifugal pump with automatic air release valve

ABSTRACT

An automatic air release valve is connected to the discharge side of a self-priming centrifugal pump for venting air from the pumping system during the priming cycle. The valve automatically closes upon completion of the priming cycle to prevent venting of liquid during the pumping cycle. A flow responsive actuator maintains the valve closed.

llnitefi States Patent [191 Porter et a1.

SELF-PRIMING CENTRIFUGAL PUMP WITH AUTOMATIC AIR RELEASE VALVEInventors: Robert J. Porter, Mansfield; Stanley B. McFarlin,Jeromesville, both of Ohio Assignee: The Gorman-Rupp Company,

Mansfield, Ohio Filed: Feb. 22, 1971 Appl. 15103117392 Related US.Application Data Continuation-impart of Ser. No. 773,549, Nov. 5, 1968,Pat. No. 3,575,521.

US. Cl 415/11, 415/27, 137/117 Int. Cl. F04d 9/00, F04d 27/02 Field ofSearch 415/11, 27, 26;

I References Cited UNITED STATES PATENTS 5/1961 Wiegers' 137/119 1 June26, 1973 3,320,680 5/1967 Paschke et al 251/140 3,434,430 3/1969 Bermanet al. 415/11 3,575,521 4/1971 Porter et a1 415/27 PrimaryExaminer-l-lenry F. Raduazo Attorney-Watts, Hoffmann, Fisher & l-leinke[5 7] ABSTRACT An automatic air release valve is connected to thedischarge side of a self-priming centrifugal pump for venting air fromthe pumping system during the priming cycle. The valve automaticallycloses upon completion of the priming cycle to prevent venting of liquidduring the pumping cycle. A flow responsive actuator maintains the valveclosed.

11 Claims, 15 Drawing Figures PAIENTEUJuHzBJsn Fig. I

INVENTOR 5 POBERT J. PORTER BY STANLEY 5. McFAEL/N W 7 I a in ATTORNEYS.

PATENIEUJUHZBIHB 3.141; 615

SHEEI 2 OF 5 INVENTORS. ROBERT J. POQTEE BY STHNLEY 5. MFAQL/N M; Q/m'ZIMI VI) 4 TTOENE Y5.

Costs.

SELF-PRIMING CENTRIFUGAL PUMP WITH AUTOMATIC AIR RELEASE VALVE CROSSREFERENCED PATENT This is a continuation-in-part of United States patentapplication Ser. No. 773,549 filed Nov. 5, 1968 by Robert 1. Porter andStanley B. McFarlin entitled SELF-PRIMING CENTRIFUGAL PUMP WITH AU-TOMATIC AIR RELEASE VALVE, now U.S. Pat. No. 3,575,521.

BACKGROUND OF THE INVENTION The present invention relates generally tothe centrifugal pump art, and more particularly to pumping systemsincluding a self-priming centrifugal pump and an automatic air releasevalve connected to the discharge side of the pump for venting air fromthe system during the priming cycle.

During the priming cycle of a centrifugal self-priming pump, the air orgas in the pump suction line is evacuated to provide the suction lift.In so-called force main systems in which a head of liquid is maintainedin the discharge line downstream from the pump, suitable provision mustbe made for venting such air or gas from the pumping system.

It has been conventional to provide centrifugal pumping systems with aconstantly open vent communicating with the discharge side of the pump.One typical vent structure which has been used is a flow restrictordevice comprising a closed cylindrical housing having a tangential inletcommunicating with the pump discharge line and an axial outletcommunicating with a sump or a return line or the like.

- The gas or air evacuated from the pump suction lines during thepriming cycle is vented through the flow restrictor together with'aportion of the liquid which is forced from the discharge chamber of thepump. After the pump has been fully primed pumped liquid flows throughthe flow restrictor during the entire time that the pump is inoperation.

The flow restrictor of the prior art is constructed to minimize the flowof liquid therethrough during the pumping cycle. Nevertheless, theconstant venting of a portion of the liquid being pumped through theflow restrictor is both wasteful and expensive and decreases theefficiency of the pump.

Another disadvantage of 'many of the prior art vent arrangements is thatthey are subject to malfunction under conditions which may result inclogging of the vent lines. Centrifugal pumps are often used to handleliquids containing heavy concentrations of foreign materials or solidswhich tend to clog the vent lines and the flow restrictor itself andthereby prolong or even prevent priming. Furthermore, the closed housingof the conventional flow restrictor devicedescribed above is difficultto clean and is responsible for increased SUMMARY OF THE INVENTION Thepresent invention provides a new and improved air venting valve for aself-priming pumping system in which a flow actuated vent valving memberis moved toward a position in which venting terminates byfluid flow inthe system and wherein a flow responsive actuator complements operationof the valving member to assure that the valving member closescompletely when the pump is primed.

The new air release valve is associated with the discharge side of acentrifugal pump for encouraging pump priming while minimizinginefficiencies connected with continuously venting systems. The valve isopen during the priming cycle to vent the air or gas evacuated from thepump suction lines and automatically closes when the pump is fullyprimed. This avoids venting liquid during the pumping cycle.

The air release valve is responsive to the conditions of fluid flowthrough it so that the valve remains open so long as pumped fluid flowis below a given level. When the pump output flow rate reaches apredetermined level, indicating the pump is primed, the valve closes.

The air release valve comprises a housing which defines a vortex chamberhaving a tangential inlet and a relatively larger axial outlet. Avalving member is mounted in the housing and is biased to a normallyopen position permitting flows of gas or mixtures of gas and liquidthrough the valve. The valving member is movable from its open positionto a closed position in response to liquid flow.

The valving member is preferably biased to its open position by aspring. The biasing spring force acting on the valving member isadjustable so that the valving member closes at a particular conditionpoint of the pumping system; that is, the point at which the pumpcommences to pump liquid at the rated capacity and head.

When a pumping cycle is completed and the pump is shut off, the valve isautomatically opened by the biasing spring force. If for any reason thesuction head is lost before the next pumping cycle, the valve remainsopen upon reactuation of the pump until a full prime is attained,whereupon the valve again automatically closes. If pump suction head isnot lost, the valve closes immediately when the pump is started.

The biasing spring force is adjustable so that the air release valvecloses at a desired pump discharge flow rate depending on the pumpingsystem in which it is used. That is to say, individual systems producedifferent liquid flow rates through the venting valves when the systempump is primed. The valve is adjusted to close when this primed flowrate occurs.

The new venting valve is constructed and arranged so that once the pumpis primed and operating the valve is maintained closed notwithstandingvariations in pump operation pressures or flow rates which may occurduring normal operation of a pumping system over a period of time. Thenew valve thus insures against any tendency for the valving member tohunt," i.e. periodically move between positions, or otherwise fail toclose completely due to such pressure or flow variations.

In a preferred construction, a flow responsive actuator is associatedwith the valving member to assure that the valving member is maintainedin its closed position when the pump is primed during the pumping cycle.The actuator comprises a solenoid coil which has an armature in forcetransmitting relationship with the valving member. The energizationcircuit for the solenoid coil includes a control switch which completesthe circuit when the pump is primed. In one preferred system, a checkvalve is located downstream from the pump and the air venting valve. Thecheck valve opens in response to pump discharge pressure when the pumpis primed. When the pump is at its condition point the check valve isfully opened. The control switch is actuated to its closed position bymovement of the check valve toward the open position and when the checkvalve closes the control, switch is opened to interrupt the solenoidenergizing circuit.

One preferred control switch includes an operating arm actuated by amovable part of the check valve. The operating arm is resilientlydefiectable and is situated so that the control switch closes before thepump discharge pressure and flow conditions reach the condition pointlevels. The operating arm deflects after the switch is initially closedso that the switch is maintained closed as the discharge pressure andflow conditions proceed to the condition point levels. Thereafter, ifthe pressure or flow levels should vary somewhat from the conditionpoint, the switch operating arm maintains the switch contacts closed.

In another preferred construction, the switch is a mercury switchmounted on a movable part of the check valve. As the pressure and flowlevels increase toward the condition point levels the mercury switch istipped and closes just prior to the check valve opening fully. Themercury switch remains closed throughout a range of system operatingflow conditions.

Another preferred construction employs a switch formed by a pressureactuated contact arm which engages a second movable contact armthroughout a range of detected pump discharge pressures. The pressureactuated arm can be driven, for example, by a Bourdon tube gauge needledriving mechanism. The Bourdon tube communicates with the pump dischargepipe via a suitable pressure fitting.

A principal object of the invention is the provision of a new andimproved self-priming pumping system including a flow actuated airrelease valve which is open to vent part of the system while a pump isbeing primed and wherein the air release valve is closed in response toliquid flowing through it at a predetermined rate and is maintainedclosed after the pump is primed by a flow condition responsive actuator.

Other objects, features and advantages of the invention will be apparentfrom the following detailed de scription made with reference to theaccompanying drawings which form part of the specification.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic illustration ofa pumping system embodying an air release valve forming part of theinvention;

FIG. 2 is a cross sectional view of the air release valve embodied inthe system illustrated in FIG. 1 having portions shown in elevation andon a scale larger than the scale of FIG. 1;

FIG. 3 is a cross-sectional view taken on the line 3-3 of FIG. 2;

FIG. 4 is a cross-sectional, fragmentary view of a modified air releasevalve including check valve structure;

FIG. 5 is a cross-sectional view taken on the line 5-5 of FIG. 4;

' FIG. 6 is a cross-sectional view of a portion of the valve of FIG. 4;

FIG. 7 is a view similar to FIG. 4 illustrating another modified airrelease valve construction including check valve structure;

FIG. 8 is a view taken on the line 8-8 of FIG. 7;

FIG. 9 is an elevational view with portions broken away of still anothermodified valve construction;

FIG. 10 is a view taken on the line 10-10 of FIG. 9;

FIG. 1 1 is a view of a portion of still another modified valveconstructed according to the invention;

FIG. 12 is an elevational view of still another modified valveconstructed according to the invention;

FIG. 13 is a schematic view of another modified system employing asupplemental actuator for a flow actuated air release valve;

FIG. 14 shows a modification of part of the system of FIG. 13; and,

FIG. 15 shows another modification of part of the system of FIG. 13.

DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring now to the drawings,and to FIG. 1 in particular, there is shown a conventional centrifugalselfpriming pump 10 which includes a casing having a rear wall 11, afront wall 12, and a partition wall 13. The walls of the casingcooperate to define a suction chamber 14 and a discharge chamber 15. Animpeller 16 is disposed within the pump casing and is supported on ashaft 17 which extends rearwardly through the rear casing wall 11 and isconnected to a suitable motor 18.

An inlet pipe fitting 25 is connected to the front wall 12 of the casingand opens into the suction chamber 14 through a hole in the front wallwhich is equipped with a suction check valve 26. An outlet pipe fitting27 also is connected to the casing and opens into discharge chamber 15.

The pump 10 is illustrated as being embodied in a socalled force mainsystem in which a static condition of liquid is maintained at all timesin the discharge line of the pump. The system includes an inlet pipe 35which is connected to the inlet fitting 25 and extends down into asuitable reservoir or tank 36 containing the liquid to be pumped. Adischarge pipe 37 is connected to the discharge fitting 27 and extendsupwardly from the pump 10. This discharge line 37 is equipped with acheck valve 38 downstream from the pump 10 which serves to maintain astatic head of liquid in the discharge pipe above the valve 38 when thepump 10 is not operating at rated capacity and head.

When the pump 10 has been fully primed and is operating in its pumpingcycle at rated capacity and head, a column of liquid is maintained inthe suction inlet pipe 35 and a vacuum exists in the suction chamber 14above the level of liquid therein. The impeller 16 operates to pump theliquid from the suction chamber 14 into the discharge chamber 15 and outof the pump 10 through the discharge line 37 and then through the checkvalve 38.

During the priming cycle of the pump 10, which will occur upon initialoperation of the pump and when, for some reason, the suction head islost between pumping cycles, air or gas will be contained in the inletpipe 35 and in the chamber 14 of the pump. When the pump 10 is ready forpriming, a quantity of liquid is contained in the suction and dischargechambers somewhat as indicated in FIG. 1. The pump motor 18 is energizedto start rotation of the impeller 16 to move a quantity of the liquidand air from the suction chamber 14 into the discharge chamber 15, thuscreating a partial vacuum on the suction side of the pump. Atmosphericpressure exerted on the liquid to be pumped forces the liquid up theinlet pipe 35 to a height depending upon the volume of liquid pumped outof the suction chamber and the internal dimension of the pipe 35. Insome applications, the liquid may rise four to five feet up the pipe 35each time the liquid is pumped out of the suction chamber. Continuedactuation of the impeller 16 continues to move quantities of liquid andair from the suc' tion chamber into the discharge chamber, thus causingthe height of the liquid in the pipe 35 to progressively increase. Thepriming cycle is completed when a vacuum has been established in thesuction chamber 14 and the pump is operating at its rated capacity andhead.

It will be apparent from the foregoing description that it is necessaryto vent the air or gas which is pumped by the impeller 16 into thedischarge chamber during the priming cycle so that the pressure in thedischarge chamber remains relatively low. Such air or gas cannot beforced through the main discharge line 37 past the valve 38 because ofthe relatively larger static pressure of the liquid which is maintainedin the discharge line downstream from the valve. In order to vent theair or gas which is evacuated from the suction inlet pipe 35 and thechamber 14 during the priming cycle, the invention provides a new airrelease valve assembly 45 which is connected to the discharge pipe 37between the discharge side of the pump and the valve 38. As generallyexplained above, the new air release valve 45 is open during the primingcycle to vent the air or gas evacuated from the suction inlet line andautomatically closes at the end of the priming cycle to pre vent theventing of liquid through the valve 45 during the pumping cycle.

Referring now to FIGS. 2 and 3, the new air release valve assembly 45 isshown to comprise a valve body housing 46 including a cup-like basemember 47 and a cover 48 removably attached to the base member. The basemember 47 carries studs 49 which are threaded into the rim 50 of thebase member at spaced locations around its circumference and whichproject upwardly through openings in the cover '48 near its periphery.Wing nuts 51 or the like are threaded on the upper ends of the studs 49to hold the cover 48 in place. The wing nuts 51 permit the cover 48 tobe quickly removed from the base member 47 so that the valve housing 46can be easily cleaned whenever necessary. A suitable O-ring seal 52 isprovided between the cover 48 and the rim 50 of the base member 47 toprevent leakage of fluid between these parts.

The interior of the housing 46 formed by the members 47, 48 defines agenerally cylindrical vortex chamber 54. At least one inlet port 55 isformed through the side wall or rim 50 of the base member 47 to directfluid tangentially into the vortex chamber 54. As is most clearly shownin FIG. 3, the inlet port 55 is formed through an external cornerstructure 56 which is part of the base member side wall.

An inlet line 57 is connected to the discharge line 37 and communicateswith the inlet port 55. In the preferred construction of the invention,a second tangential inlet port 60 is formed through the corner structure56 into communication with the vortex chamber 54 at right angles to theinlet 55. The two ports 55 and 60, only one of which is used, permiteither right or left hand installation of the valve 45. The inlet portwhich is not in use, for example, the port 60, is normally closed by asuitable threaded plug 61 and may serve as a drain when the plug isremoved. The valve body housing 46 is also provided with an outlet port62 which extends axially from the vortex chamber 54 through a centrallylocated, outwardly extending boss 63 of the base member 47. The outletport 62 may be connected to an outlet or discharge line 64 by atransparent nipple 65 which is threaded into the boss 63. As more fullyexplained below, observation of liquid flow through the transparentnipple 65 facilitates proper adjustment of the valve 45.

A valve seat ring 66 having a frusto-conical seating surface 67 ismounted in a recess formed in the bottom of the base member 47 aroundthe mouth of the outlet port 62. As shown, an O-ring 68 is carried in aperipheral groove formed in the side wall of the seat ring 66 and isdisposed in sealing engagement with the side wall of the recess in whichthe seat ring is mounted. In the preferred construction of the valve 45,a resilient backup ring 69 is disposed between the seat ring 66 and thebottom of the recess in which the seat ring is mounted. The back-up ring69 permits limited floating movement of the seat ring 66 to assurecomplete closing of the outlet port 62 as described presently.

A valving member is carried by the housing cover 48 for movement axiallyof the housing into and away from engagement with the valve seat ring 66for opening and closing the outlet port 62. The valving member 75 has astem portion 76 and a head 77. The head 77 is formed to have a generallyhemispherical or domelike upper portion 78 and a generallyfrusto-conical lower portion 79 which converges from the upper portion78 to the bottom of the head, as viewed in FIG, 2. The frusto-conicalportion 79 is engageable with the seating surface 67 of the seat ring 66to close the outlet port 62.

In the illustrated embodiment of the invention, the stem 76 of thevalving member 75 extends through a central, axially outwardlyprojecting hub portion 80 of the housing cover 48. A bushing 81 isthreaded into the inner end of the hub portion 80 around the stem 76 andserves to support the valving member 75 for sliding movement between itsopen and closed positions. The valving member 75 is urged to a normallyopen position by a spring 82 which is connected to the end of the stem76 and to the end of an adjustment screw 83. The spring 82 and theadjustment screw 83 are disposed within a sleeve 84 which has one endthreaded into the hub 80 and its opposite end closed by a cap 85. Theadjustment screw 83 extends outwardly through a threaded opening in thecap 85, and a locknut 86 and a suitable sealing washer 87 are carried onthe adjustment screw for engagement with the outer surface of the cap85.

The outwardly projecting end of the adjustment screw 83 is shown ashaving a slot 88 suitable for receiving a screw driver of the likewhereby the adjustment screw 83 can be rotated to advance it in and outof the sleeve 84. Selective adjustment of the screw 83 serves to varythe tension of the spring 82, thereby changing the biasing force urgingthe valve member 75 to its normally open position.

The operation of the valve 45 is dependent upon the creation of apressure differential across the housing with the inlet pressure beinggreater than the outlet pressure. To this end, the outlet port 62 of thehousing 46 is made larger than the inlet port. In the preferredconstruction of the valve, the outlet port 62 has a diameter which ispreferably 25% larger than that of the inlet port. In order to preventdebris, such as rags and other solids, from clogging the inlet port ofthe valve, it has been found desirable to form the inlet port with a oneinch diameter. Thus, in a valve construction having a one inch inletport, the outlet port should preferably be one and one quarter inches indiameter.

When fluid is introduced into the valve 45 through one of the inletports 55 or 60, a vortex flow is created within the chamber 54 so thatthe fluid swirls inwardly of the housing across the inner surface of thecover 48. This vortex flow of fluid is such that the pressure at theupper hemispherical portion of the valve head 77 is greater than thepressure on the frusto-conical lower portion 79. As the flow rate ofliquid into the chamber 54 increases, the pressure differential acrossthe head 77 also increases to gradually pull the valving member 75 intoengagement with the seat ring 66 against the biasing force of the spring82 thereby closing the outlet port 62. By adjusting the tension of thespring 82, the valving member 75 can be made to close upon any desiredcondition of liquid flow through the housing 46.

The operation of the valve 45 in the illustrated pumping system will belargely apparent from the foregoing description. Assuming that the pump10 is unprimed, the valve 45 will remain in its normally open positionwhen the pump motor is turned on to initiate the priming cycle describedabove so that the air and fluid evacuated from the pump suction linesand discharged from the pumping chamber can flow through the open valve45 and the connected outlet line 64. As the flow of liquid through thevalve 45 increases during the priming cycle, the valving member 75 willbe pulled toward the seat ring 66 against the biasing force of thespring 82. When the priming cycle has been completed and the pump 10 isoperating at rated capacity and head, the liquid flowing through thevalve will pull the valving member 75 to its fully closed position,thereby preventing any further discharge of liquid through the valveduring the pumping cycle. When the pump motor is shut off at the end ofthe pumping cycle the valve 45 will automatically open, but will closeimmediately when the pump is restarted if the pump suction has not beelost. If for some reason the pump suction is lost before restarting thepump, the valve will remain open to allow the pump to recycle and willclose when full prime has again been attained.

An important feature of the invention resides in the construction whichpermits the valve 45 to be adjusted to operate at the condition point ofany pumping system, which condition point varies from system to systemdepending upon such factors as the pressure drop in the pipes or lines,the output capacity of the system, etc. The spring-loaded valving member75 may be adjusted to close at the condition point of the system inwhich it is installed by loosening the locknut 86 and turning theadjustment screw 83. Inward adjustment of the screw 83 decreases thetension of the spring 82 so that the valving member 75 can close quicklyunder conditions of low head. Outward adjustment of the screw 83increases the spring tension and the closing time of the valving member,as is required under conditions of the high head.

The spring loaded valving member 75 is preferably adjusted after thepump has been operated to complete its first priming cycle. Suchadjustment is facilitated by the transparent nipple 65 connected to theoutlet of the valve 45. The priming cycle is completed when full liquidflow is observed through the nipple, and at that time the tension of thespring 82 is properly adjusted so that the valving member closes andremains closed during the pumping cycle. When adjusted, the valve 45will operate automatically during subsequent cycles of the pump and nofurther attention is required.

Reference is now made to FIGS. 412 which illustrate different checkvalve arrangements which may be associated with the air release valve 45for the purpose of preventing a reverse flow of air through the valve 45into the pumping chamber 15 when the pump is not in operation. Aspreviously described, the valve 45 opens automatically at the conclusionof each pumping cycle. Any reverse flow of air through the valve whenthe pump has been stopped could result in a loss of pump suction if thesuction valve 26 is not completely closed. The check valve arrangementsof FIGS. 4-12 insure against loss of pump suction by blocking reverseflow of air through the valve 45 when it is open.

Referring particularly to FIGS. 4-6 there is shown a check valveconstruction which is disposed in the vortex chamber of the pump 45 andadapted to block the inlet port 55 when the pressure in the vortexchamber 54 approaches the pressure in the inlet line 57. The check valveassembly 115 includes a rectangular padlike check valve member 116 ofresilient rubber-like material which extends across ports 55, 60 sothat, when the check valve member 116 is in the position illustrated inFIG. 4, air flow from the vortex chamber through the inlet 57 isprevented. The check valve member 116 is urged to its closed position bya spring construction including spring strips 120, 121 which are formedof suitable corrosion resistant material, such as stainless steel, andconnected to the member 116 by rivets 122. The check valve member 116and the spring strips 120, 121 are supported in the chamber 54 by apintle 125, the ends of which are received in cylindrical cavities 126,127 formed in the cover and base of the valve 45 respectively. Thespring strip 121 is bent to define a loop 130 medially of its endsthrough which the pintle extends.

FIG. 6 illustrates the check valve construction 115 in a relaxedcondition. It is apparent that when the check valve construction ismounted in the chamber the spring strips 120, 121 are deflected fromtheir relaxed conditions and urge the check valve member 116 firmlyagainst the side wall of the chamber. Accordingly the check memberprevents flow from the vortex chamber through the inlet line 57 when thefluid pressure force in the vortex chamber and the force of the springs120, 121 are greater than the pressure force ex erted on the valvemember by the fluid pressure in the inlet port 55.

The check valve construction 115 permits tangential flows of gas and theliquid into the vortex chamber 54 regardless of whether the flow isintroduced through the inlet port 55 or the inlet port 60. When flow isdirected into the chamber 54 through the inlet port 55, the end 131 ofthe check valve member 116 is deflected toward the center of thechamber. The opposite end 132 of the check valve member is maintained inthe closed position. If the flow is directed into the chamber throughthe inlet port 60 the end 132 is deflected into the vortex chamber 54while the end 131 remains stationary.

FIGS. 7 and 8 illustrate a modified check valve assembly 135 disposed inthe vortex chamber 54. The check valve assembly 135 includes aflapper-like valve member 136 in the form of a rectangular strip ofrubber-like material positioned across the inlet ports 55, 60 andsupported in position by a clamp 137. The clamp 137 is connected-to theside wall of the vortex chamber by screws 142 extending into tappedholes 145a in the side wall which cause the clamp to tightly grip thevalve member 136.

The inherent resilience of thevalve member 136 normally maintains itclosed across the inlet ports 55, 60 (see FIG. 7). The end 143 of thevalve member is deflected into the vortex chamber 54 only in response'tofluid flow into the chamber through the inlet port 55.

In applications in which fluid is introduced through the port 60 thecheck valve assembly 135 is turned end for end in the chamber and thescrews 142 are threaded into holes 1451) so that fluid flow from theinlet port 60 is directed tangentially into the vortex chamber past thefree end of the valve member.

FIGS. 9 and illustrate a gas venting assembly valve 45 utilizing a duckbill type check valve 150 for preventing reverse air flow through thevalve 45. The check valve 150 is formed of a rubber-like material andincludes a pair of lips 151, 152 and an integral annular flange 153. Thecheck valve 150 is held in position by engagement of the flange 153below the seat ring 66 so that the lips 151, 152 can close the outletport 62. The flow of liquid through the valve 45 forces the lips 151,152 apart permitting relatively unimpeded flow of the fluid to thedischarge pipe 64. When the pressure in the discharge pipe is equal toor greater than the pressure in the chamber, the lips 151, 152 movetogether to close the outlet port 62 and prevent air flow from the pipe64 into the chamber 54.

FIG. 11 illustrates a modified check valve 150' which is substantiallythe same as the check valve 150 FIGS. 9 and 10 except that four lips160-163 are provided. The modified valve 150' is disposed in the airrelease valve 45 in the same manner as the valve 150, and, since itoperates substantially in the same manner as the check valve 150,further description is believed unnecessary.

FIG. 12 illustrates a further modified air release valve 45 includingswing-type check valves 170, 171 in the inlet and outlet lines 57, 64respectively. Each valve assembly includes a housing 173 which supportsa swingtype valve member 174 rotatable about a hinged support 175 in thehousing. The valve member 174 moves about a pivot axis 176 to permitflow from the pipe 57 through the valve 45 to the outlet pipe 64. Thevalve member closes to prevent flow in the opposite direction and in theillustrated construction is moved to the closed position by gravity.Although two check valves 170 are illustrated in FIG. 12, inpractice,only one of these check valves is necessary to prevent the reverse flowof air through the valve 45.

A modified force main pumping system 200 is illustrated in FIG. 13.The'system 200 comprises a pump 202, a pump inlet pipe;204 and a pumpdischarge pipe 206. The pump 202 draws liquid upwardly through the inletpipe 204 and forces the liquid through the discharge pipe 206 via adischarge check valve 208. An air release valve assembly 210communicates with the dis charge pipe 206 between the check valve 208and the pump 202. When the pump is being primed and the check valve 208is closed, air or other gas in the pump is vented to atmosphere. Thisenables the pump to be primed. When the pump is primed and operating,the air release valve 210 closes so that pumped liquid from thedischarge pipe cannot vent from the system. The pump 202 may be of anysuitable or conventional construction and can be the same as the pump 10described above in reference to FIGS. 1-12.

The check valve 208 functions the same as the check valve 38 referred toin connection with FIG. 1. That is, when the pump is not operating, thecheck valve 208 is closed to maintain a head of liquid in the dischargepipe above the check valve. The valve 208 remains closed during primingof the pump to allow the pump to vent air through the air release valve.When the pump is primed and operating the discharge pressure opens thecheck valve 208 and liquid is pumped through the discharge pipe.

The check valve 208 comprises a tubular valve housing 212 integral withthe pump discharge pipe and a movable valve member 214 which is disposedin the valve housing 212 for movement between a closed position,illustrated in FIG. 13, and an open position in which pumped liquidpasses upwardly through the valve housing and the discharge pipe 206.The valve member 214 is fixed on a pivot shaft 216 which is journalledin the valve housing 212.

The valve member 214 is biased to its closed position. The pivot shaft216 carries a lever arm 218 which is connected to the shaft on theexterior of the valve housing. The lever arm 218 is connected to areturn spring 220 which is preferably a helical tension spring havingits opposite end anchored to the housing 212. The spring 220 maintainsthe lever arm and valve plate member 214 in the positions correspondingto the closed position of the valve.

The air release valve unit 210 is connected between the pump and thecheck valve 208 for venting the discharge pipe when the pump is priming.The valve unit 210 comprises a cylindrical valve housing 222 whichdefines'a cylindrical vortex chamber 224. An inlet pipe 226 extendsbetween the pump discharge pipe 206 and the housing 222. The inlet pipeopens tangentially into the cylindrical chamber. An outlet pipe 228extends the the housing 222 along the axis of the cylindrical chamber sothat the liquid flowing through the chamber forms a vortex having itscenter located over an output port 230 in the lower wall of the chamberalong the axis of the housing. The housing 222 and associated parts thusfar described are shown schematically and may be the same as isdescribed in reference to FIGS. 1-13.

Flow through the chamber 224 is controlled by a flow actuated valvemember 232 movably disposed in the housing 222. The valve member 232includes a head portion 234 disposed in the vortex chamber and acylindrical valve stem 236 which projects through an opening 238 in theupper wall of the housing. A seal 240 surrounds the valve stem 236 andprevents the escape of liquid from the chamber between the valve bodyand the housing 222. The valve member 232 'moves in the housing so thatthe head 234 blocks the outlet port 230 and terminates flow through thechamber. The valve member 232 is biased towards its open position by'aspring 242. The biasing spring 242 is preferably a helical compressionspring which surrounds the valve stem and is compressed between a bossarea 244 surrounding the opening 238 and an annular collar 246 which iscarried on the valve stem. The collar 246 is movable along the valvestem by a suitable screw thread adjusting arrangement which is notillustrated in detail. The general operation of the air venting valveunit 210 as thus far described is the same as has been described inreference to FIGS. 1-12.

The modified system 200 differs in that operation of the air releasevalve unit is augmented by a flow condition responsive actuator 250which applies a positive valve actuating force to the valve member 232in response to predetermined flow conditions of the liquid in the pumpdischarge pipe. As is illustrated in FIG. 13, the actuator 250 includesa solenoid coil assembly 252 which is connected across a suitableelectrical power supply (not shown) by conductors 256, 258 in serieswith a control switch 260. An armature 261 of the solenoid assembly isconnected to the valve stem 236 so that when the solenoid coil 252 isenergized the armature 261 is pulled in and forces the valve stem to aposition in which the head 234 covers the outlet port 230.

In the illustrated embodiment, the control switch 260 is preferably anormally open switch of the micro switch type which is mounted adjacentthe lever arm 218. The contacts of the switch 260 are actuated to theclosed position by a cat-whisker spring lever 262 which is positionedfor engagement by the lever arm 218 whenever the check valve 208 hasmoved from the closed position toward a predetermined at least partlyopen position.

As noted above, the valve 208 does not open at all until the pumpdischarge liquid pressure is greater than the head pressure of theliquid standing over the check valve 208. When this occurs the pump isprimed and flow through the valve housing 212 opens the valve 208. Whenthe valve member 214 has moved a predetermined amount from the closedposition the catwhisker spring lever 262 is engaged by the lever arm 218and the switch 260 closes. This energizes the solenoid 252 to force thevalve member 232 to its closed position, if it is not already closed.The actuator 250 thereafter prevents the valve member from moving fromits closed position.

The lever arm 218 maintains engagement with the spring lever 262 so thatthe solenoid remains energized so long as the pump is primed and ispumping at about its operating condition to force liquid upwardlythrough the discharge pipe. In the event the pump discharge pressure ismomentarily reduced for any reason, the check valve 208 will move towardits closed position. So long as the discharge pressure does not dropbelow a predetermined level, the lever arm 218 maintains contact withthe spring lever 262 so that the solenoid assembly 252 is maintainedenergized through the range of pump discharge pressures.

An alternate switch 270 is illustrated in FIG. 14 for controlling thesolenoid assembly 252. The switch 270 is a pressure responsive switchhaving rotatable contact arms 272, 274. The contact arms 272, 274 areconnected in an energizing circuit for the solenoid 252 so that when thearms are engaged the solenoid is energized and when the arms aredisengaged the solenoid is deenergized. The contact arm 272 is mountedon a rock shaft 276 which is in turn connected to a Bourdon tube gaugeneedle actuator 278 which is shown schematically. The actuator 278 maybe of any suitable well-known construction and is therefore notdescribed in detail. The Bourdon tube of the actuator 278 communicateswith the pump discharge pipe through a pressure fitting 280. When thepump discharge pressure increases, the contact arm 272 is rotatedclockwise as seen in FIG. 14 with the amount of rotation of the armbeing proportional to the pressure level.

When the pump is primed, the liquid pressure in the discharge pipeincreases toward the condition point pressure level causing the contactarm 272 to rotate clockwise as shown in FIG. 14. The contact arm 274 hasa rest position, shown in FIG. 14, at which the arm 274 remains duringthe priming cycle. When the pump is primed and the discharge pressureincreases toward the condition point level the arm 272 engages the arm274 at its rest position whereupon the solenoid 252 is energized. As thedischarge pressure continues to increase, the arm 272 moves the contactarm 274 clockwise from its rest position maintaining the solenoid 2S2energized. The contact arm 272 has a finger 281 which extends into theplane of the contact arm 274 to assure engagement between the contactarms. The switch contact arm 274 is connected to a shaft 282 which isrotatably supported adjacent the shaft 276. The shaft 282 and the arm274 are biased toward the rest position of the arm so that when thedischarge pressure is reduced, the arm 274 and the shaft 282 movecounterclockwise toward the rest position. The arm 274 can be adjustedcircumferentially on the shaft 282 so that the rest position assumed bythe contact arm 274 is adjustable. As is shown in FIG. 14, the arm 274is set to be engaged by the arm 272 when the pump discharge pressuremoves the arm 272 to extend along the line 286. As the pressurecontinues to increase, the arms 272, 274 are maintained in engagement sothat the solenoid 252 is maintained energized to positively close theair release valve. The pump reaches its operating point when the arm 272extends along the line 288.

Since the switch arm 274 is biased toward its position illustrated inFIG. 14, any momentary reductions in the pump discharge pressure fromthe condition point level do not open the switch so long as thedischarge pressure remains in the range between the lines 286, 288indicated by the arrow 289.

FIG. 15 illustrates another alternate switching arrangement employing amercury switch assembly 290 for controlling the solenoid assembly 252.The switch assembly 290 comprises a housing 292 which is connected tothe lever arm 218 by a bracket 294. The housing 292 defines a chamber296 in which contacts 298, 300 are positioned at one end. A mass ofmercury 302 is disposed in the chamber 296 and is free to move back andforth in the chamber as the chamber is tilted relative to horizontal.The bracket 294 is adjustable to enable the orientation of the housing292 to be adjusted as desired relative to horizontal. When the checkvalve member has opened a predetermined amount, the mercury mass 302moves under influence of gravity to engage the contacts 298, 300 andthereby complete an electrical energizing circuit for the solenoid coilassembly 2S2 resulting in the valve member being urged into closedposition by the armature 261.

It can now be seen that the objects heretofore enumerated and othershave been accomplished and that a new air release valve combined with apump has been provided which vents gas from the pump discharge duringpriming and automatically closes to prevent pumped liquid from ventingwhen the pump operates at rated head and capacity. While a number ofdifferent embodiments of the invention have been illustrated anddescribed, the invention is not to be considered limited to the preciseconstructions disclosed. it is intended that all adaptations,modifications and uses of the invention falling within the scope of theappended claims be covered.

We claim:

1. In combination with a pump having inlet means and outlet means, anair release valve assembly comprising:

a. a chamber;

b. said chamber having an outlet port;

c. chamber inlet means communicating said chamber with said pump outletmeans;

d. valving means including;

1. a valve seat in said chamber surrounding said outlet port;

2. a valve member movably supported in said chamber; and,

3. biasing means urging said valve member toward an open position spacedfrom said seat;

e. said valving means having a closed position wherein said valve memberis in engagement with said seat to block fluid flow through said outletport; said chamber inlet means directing pump effluent into said chamberalong a flow path for impingement on said valve member to create apressure force on said valve member urging said valve member toward saidclosed position; and,

g. actuator means associated with said valve member for moving saidvalve member to said closed position in response to liquid flowconditions through said pump outlet means.

2. A pump as claimed in claim 1 wherein said actuator means comprises anelectrically energized actuator element, a control switch in circuitrelation with said actuator element, and means for actuating saidcontrol switch in response to flow conditions in said pump outlet means.

3. A pump as claimed in claim 2 wherein said pump outlet means includesa check valve having means movable between open and closed positions,said control switch being operated in response to movement of said checkvalve means.

4. The pump claimed in claim 2 wherein said means for actuating saidcontrol switch includes a member which is movable in proportion topressure of liquid in said pump outlet means.

5. In combination:

a. pump means operable through a priming cycle and a pumping cycle, saidpump means including an inlet opening and an outlet opening;

b. discharge valve means connected to said outlet opening for permittingfluid flow therethrough during said pumping cycle and for blocking fluidflow therethrough during said priming cycle;

c. air release valve means connected between said pump outlet openingand said discharge valve means for permitting fluid flow therethroughduring said priming cycle and blocking fluid flow therethrough duringsaid pumping cycle, said air release valve means comprising;

1. a valve housing defining a vortex chamber having a cylindricalchamber wall portion;

2. means defining a valve inlet opening for directing pump effluent intosaid chamber substantially tangentially along said wall portion tocreate vorticular flow in said chamber;-

3. an axial valve outlet opening from said chamber;

4. a valve seat surrounding said valve chamber;

5. a valving member supported by said housing for movement toward andaway from said valve seat, said valving member being biased away fromsaid seat and including a surface portion impinged upon by vorticularflow of pump effluent in said chamber which moves said valving membertoward said valve seat; and,

d. an actuator for urging said valving member toward engagement withsaid seat in response to sensed pump outlet liquid conditions wherebywhen said pump means is primed said air release valve is maintainedclosed.

6. The combination claimed in claim 5 wherein said discharge valve meanscomprises a check valve member which opens only during said pumpingcycle, and means for operating said actuator means in response tomovement of said check valve member toward an open position.

7. The combination claimed in claim 6 wherein said actuator means iselectrically energized through a control circuit and said means foroperating said actuator means comprises a control switch actuated bymovement of a part connected to said check valve member away from aposition corresponding to the closed position of said check valvemember.

8. The combination claimed in claim 7 wherein said discharge valve meansfurther comprises a pivot shaft supporting said check valve member forpivotal movement between its open and closed positions, said switchactuating part connected to said pivot shaft for movement therewith.

9. The combination claimed in claim 8 wherein said control switchcomprises a mercury switch and said part comprises a bracket supportingsaid mercury switch for tipping movement relative to horizontal whensaid pivot shaft rotates.

It). The combination claimed in claim 7 wherein said discharge valvemeans further comprises a pivot shaft supporting said check valve memberfor pivotal movement, said switch actuating part connected to said pivotshaft and movable therewith to engage a switch operating lever when saidvalve member has moved a predetermined amount away from said closedposition.

Ill. The combination claimed in claim 5 further including control meansfor operating said actuator, said control means comprising at least onecontrol member which is movable in response to changes in pressure ofliquid in the vicinity of said pump outlet opening.

1. In combination with a pump having inlet means and outlet means, anair release valve assembly comprising: a. a chamber; b. said chamberhaving an outlet port; c. chamber inlet means communicating said chamberwith said pump outlet means; d. valving means including;
 1. a valve seatin said chamber surrounding said outlet port;
 2. a valve member movablysupported in said chamber; and,
 3. biasing means urging said valvemember toward an open position spaced from said seat; e. said valvingmeans having a closed position wherein said valve member is inengagement with said seat to block fluid flow through said outlet port;f. said chamber inlet means directing pump effluent into said chamberalong a flow path for impingement on said valve member to create apressure force on said valve member urging said valve member toward saidclosed position; and, g. actuator means associated with said valvemember for moving said valve member to said closed position in responseto liquid flow conditions through said pump outlet means.
 2. a valvemember movably supported in said chamber; and,
 2. A pump as claimed inclaim 1 wherein said actuator means comprises an electrically energizedactuator element, a control switch in circuit relation with saidactuator element, and means for actuating said control switch inresponse to flow conditions in said pump outlet means.
 2. means defininga valve inlet opening for directing pump effluent into said chambersubstantially tangentially along said wall portion to create vorticularflow in said chamber;
 3. an axial valve outlet opening from saidchamber;
 3. A pump as claimed in claim 2 wherein said pump outlet meansincludes a check valve having means movable between open and closedpositions, said control switch being operated in response to movement ofsaid check valve means.
 3. biasing means urging said valve member towardan open position spaced from said seat; e. said valving means having aclosed position wherein said valve member is in engagement with saidseat to block fluid flow through said outlet port; f. said chamber inletmeans directing pump effluent into said chamber along a flow path forimpingement on said valve member to create a pressure force on saidvalve member urging said valve member toward said closed position; and,g. actuator means associated with said valve member for moving saidvalve member to said closed position in response to liquid flowconditions through said pump outlet means.
 4. The pump claimed in claim2 wherein said means for actuating said control switch includes a memberwhich is mOvable in proportion to pressure of liquid in said pump outletmeans.
 4. a valve seat surrounding said valve chamber;
 5. Incombination: a. pump means operable through a priming cycle and apumping cycle, said pump means including an inlet opening and an outletopening; b. discharge valve means connected to said outlet opening forpermitting fluid flow therethrough during said pumping cycle and forblocking fluid flow therethrough during said priming cycle; c. airrelease valve means connected between said pump outlet opening and saiddischarge valve means for permitting fluid flow therethrough during saidpriming cycle and blocking fluid flow therethrough during said pumpingcycle, said air release valve means comprising;
 5. a valving membersupported by said housing for movement toward and away from said valveseat, said valving member being biased away from said seat and includinga surface portion impinged upon by vorticular flow of pump effluent insaid chamber which moves said valving member toward said valve seat;and, d. an actuator for urging said valving member toward engagementwith said seat in response to sensed pump outlet liquid conditionswhereby when said pump means is primed said air release valve ismaintained closed.
 6. The combination claimed in claim 5 wherein saiddischarge valve means comprises a check valve member which opens onlyduring said pumping cycle, and means for operating said actuator meansin response to movement of said check valve member toward an openposition.
 7. The combination claimed in claim 6 wherein said actuatormeans is electrically energized through a control circuit and said meansfor operating said actuator means comprises a control switch actuated bymovement of a part connected to said check valve member away from aposition corresponding to the closed position of said check valvemember.
 8. The combination claimed in claim 7 wherein said dischargevalve means further comprises a pivot shaft supporting said check valvemember for pivotal movement between its open and closed positions, saidswitch actuating part connected to said pivot shaft for movementtherewith.
 9. The combination claimed in claim 8 wherein said controlswitch comprises a mercury switch and said part comprises a bracketsupporting said mercury switch for tipping movement relative tohorizontal when said pivot shaft rotates.
 10. The combination claimed inclaim 7 wherein said discharge valve means further comprises a pivotshaft supporting said check valve member for pivotal movement, saidswitch actuating part connected to said pivot shaft and movabletherewith to engage a switch operating lever when said valve member hasmoved a predetermined amount away from said closed position.
 11. Thecombination claimed in claim 5 further including control means foroperating said actuator, said control means comprising at least onecontrol member which is movable in response to changes in pressure ofliquid in the vicinity of said pump outlet opening.